Pomegranate is a very ancient crop native to Southwest Asia, specifically Iran, and parts of Afghanistan and Pakistan. It has been cultivated in the Middle East for thousands of years, with evidence suggesting cultivation in Persia (modern-day Iran) as early as 3000 BC. In Azerbaijan, the pomegranate tree grows wild as a native endemic. Targeted selection, domestication, and hybridization have played an important role in the commercial cultivation of the pomegranate and contributed to the emergence of new varieties. The presence of extensive pomegranate plantations and the diversity of many indigenous, high-quality local varieties indicate that Azerbaijan is a region particularly suitable for the production of this fruit. According to 2022 data, pomegranate plantations in Azerbaijan cover 22,600 hectares. Azerbaijan can reliably enrich pomegranate plantations with valuable original varieties. By mastering modern selection methods with their enormous potential, it is now possible to update and improve older varieties in a shorter time and, using existing starting material, to create new, high-yielding, and high-quality varieties that meet all the requirements for commercial fruit production.
Pomegranate is a valuable fruit, medicinal and attractive ornamental plant.
Thanks to its rich chemical composition, the pomegranate occupies one of the leading positions among subtropical fruits. Many researchers emphasize that the pomegranate fruit is a source of valuable vitamins and trace elements: 27–52% of the fruit consists of peel, 36–75% juice, and 7–21% seeds. Pomegranate juice contains 8–20% invert sugar, 4–10% citric acid, malic acid, and oxalic acid, up to 14% vitamin C, vitamins B1, B2, B9, and B3, as well as antianthocyanins, catechins, tannins, minerals (calcium, magnesium, potassium, manganese, cobalt), bioflavonoids, and phytoncides. Pomegranate juice contains more antioxidants than any other beverage, be it red wine, green tea, blueberry, or cranberry juice. All parts of the pomegranate tree (fruits, leaves, flowers and roots) are used for medicinal purposes.
Botanical characteristics and biological properties
The Pomegranate (Punica Granatum L.) belongs to the Lythraceae family. The name pomegranate comes from the medieval Latin words pōmum "apple" and grānātum "seed". The pomegranate grows naturally as a deciduous shrub with 8–12 branches. The trunk and branches are thorny. The leaves are small, lanceolate, initially reddish-brown, later green. Flowering begins 30–40 days after the start of the growing season at an average daily temperature of 20 °C and lasts 60–90 days. Fruits and flowers are formed on short shoots at the same time, which is typical of remontant plant species. The flowers are bisexual, self-pollinated but can also be pollinated by insects. Two types of flowers are distinguished based on their appearance. The bell-shaped flowers are short and have an underdeveloped ovary. They usually occur in clusters of 3–5 flowers. Such flowers fall off without bearing fruit. The pitcher-shaped flowers appear singly, have a long pistil with a well-developed ovary, and usually develop into fruit.
The fruits are mostly spherical and large (200–500 g or more). The peel is red, pink, orange-yellow and sometimes black, depending on the variety. The pomegranate fruit is divided into 9–12 chambers separated by membranes. Each chamber contains two rows of seed coats (called arils), within which the seeds are surrounded by juicy, red pulp. One fruit contains 400–700, sometimes 1000–1200 edible seeds. The period from the beginning of the growing season to the harvest of fruits with a sum of active temperatures of 3500 °C is 5.5–6.5 months.
The pomegranate is a light-loving plant, it tolerates temporary water shortages well. The root system is strong, most of the roots are located at a depth of 40-60 cm. The remaining roots reach a depth of 1.5-2 m or more. Irrigation is necessary in areas with annual precipitation of less than 600 mm. It tolerates winter frosts down to -16 ° C. With normal care, the pomegranate lives and bears fruit for several decades. Wild pomegranate trees growing without care in nature grow in the form of a tree and live for over 120 years.
Ecological features and geographical distribution of the pomegranate
The extensive area of distribution extends from deserts to subtropics, settlement can be observed on various reliefs, exposures and soils, and the ability to quickly regenerate after freezing and drying indicates the exceptional plasticity of the pomegranate tree. The orography, soils, vegetation, climate and microclimate of Azerbaijan are very diverse. However, pomegranate is widespread in almost all regions of the republic, with the exception of high-mountainous and highly saline areas.
Pomegranates of Azerbaijani origin have gone through a long evolutionary path in cultivation and breeding and today exhibit high quality characteristics and greater polymorphism compared to endemic and transitional forms. In Azerbaijan, it is possible to observe a wide range of variations and diversity of forms, from extremely small-fruited wild forms to cultivated varieties with very large fruits and diverse characteristics.
The best pomegranates grow in areas with arid or semi-arid climates. In humid areas, the fruits are of lower quality and burst during ripening when it rains. In tropical areas, pomegranates become woody and produce only a small crop. The pomegranate tree grows in dry subtropics, but prefers coastal areas along seas and rivers. The pomegranate tree thrives best in areas with mild winters, where temperatures do not drop below -12 °C. In the absence of light, pomegranate forms long, weak branches, has few leaves and blooms poorly.
The most common pomegranate varieties worldwide
There are over 500 varieties of pomegranate, of which approximately 60 are cultivated worldwide. Here you will find a description of the most common varieties worldwide.
Azerbaijani Guleysha (Azerbaijan). Shrub of medium height (3 m), densely branched. The fruits are large (300 - 400 g), round to oblong. The peel is thin, shiny, red-pink. The arils are large, red, with medium-sized seeds. The juice is sweet and sour, tasty and bright red. It contains up to 20% sugar and 1.8% acids. The juice yield is 55%. The fruits ripen in October. The average yield from a shrub is 45 - 50 kg.
Pink Guleysha (Azerbaijan). The shrub is medium tall (3 - 4 m), densely branched. The fruits are round to elongated in shape, large (200 - 250 g), but with a low yield they reach a weight of up to 400 - 600 g. The peel is thin, creamy-pink. The arils are medium large, dark cherry in color. The juice yield is 54.5%, the sugar content is 15.6% and the acid content is 1.3%. The juice is sweet and sour. The fruits ripen in October. The yield from a shrub is 35 - 45 kg.
Gyrmyzy Guleysha (Azerbaijan). The shrub is large, sprawling. The round-shaped fruits are large (350-500 g) or medium (250-300 g) when ripe. The skin is crimson red with pronounced stripes. The arils are large, dark cherry in color, with sweet and sour juice. The juice yield is 53.5%, the sugar content is 15.5% and the acid content is 1.5%. The juice is sweet and sour. The fruits ripen in late October. The average yield from a shrub is 50-55 kg.
Gyrmyzy Gabyk (Azerbaijan). The shrub is 4 m tall, with smaller thorns. The fruits are large (350-450 g), round. The skin is medium thick and bright red. The arils are large, raspberry red. The juice is dark red, sweet and sour and very tasty. The juice yield is 52.4%, the sugar content is 14.5% and the acids are 2.1%. The fruits ripen at the end of October and are stored for 4-5 months. The productivity per shrub is 45-50 kg.
Nazik Gabyk (Azerbaijan). The shrub grows to a height of 4 m. The fruits are large (400 g) and dark red. The peel is thin. The arils are large, the juice is sweet and sour. The juice yield is 48.8%, contains 12.3% sugar and 2.6% acids. The fruits ripen in early or mid-October. 35-40 kg of fruits are harvested from each shrub. The fruits are stored for 3-4 months.
Bala Mursal (Azerbaijan). It is considered one of the best Azerbaijani varieties. The shrub reaches a height of 3 m, with a small number of thorns. The fruits are flat-spherical in shape, weighing about 300 g, light raspberry-red in color. The peel is thick. The arils are medium-sized, dark red. The juice yield is 54.3%, the juice varies from deep red to raspberry. It contains up to 16% sugar and 1.5% acids. The taste is sweet and sour. The fruits ripen in early October and are stored for 3-4 months. An average of 30-40 kg of crop is harvested from each shrub.
Shah Nar (Azerbaijan). Medium-sized, densely branched shrub. The fruits are medium-sized (300-350 g), round or pear-shaped. The peel is medium-thick, light coffee-red in color. The arils are medium-sized. The taste is pleasant, sweet and sour. The juice yield is 53.9%, contains 13.4% sugar and 2.1% acids. The fruits ripen in the second half of October. 30-35 kg of fruits are obtained from the shrub. The fruits are stored for up to 6 months.
Veles Nar (Azerbaijan). Medium-sized shrub. The fruits are medium-sized (200-250 g), round-oval. The peel is thick, light cream in color, covered with a dark brown shade, resembling the bark of a hornbeam. The arils are medium-sized, pink-red, sweet, with low acidity. The juice yield is 50.2%. The fruits ripen by the end of October and are stored for 3-4 months. Productivity is high. 40-45 kg of fruit are obtained from the shrub.
VIR No.1 (Azerbaijan). The shrub is sprawling, medium height (2.5-3 m). The flowers are large, light red. The fruits are large (350-400 g), round, sometimes pear-shaped. The peel is thick, light yellow. The arils are light red, with a pleasant taste. The juice yield is high (56.7%). The fruits ripen in late October. Approximately 45 kg of crop is harvested from each shrub.
Akdona (Uzbekistan). A popular large-seeded variety, also called Tyuyatish (camel's tooth). The shrub is large, but at the same time compact. The fruits are flat-spherical. The fruit weight is on average 250 g, sometimes reaching a weight of up to 600 g or more. The peel is smooth, shiny, light in color with a slight crimson blush. The arils are pink, the seeds are elongated. The juice is light pink, very sweet, contains about 15% sugar and about 0.6% acids. The fruits ripen in early October and are stored for about two months. The yield is 20-25 kg per shrub or more.
Kyzyl Anor (Uzbekistan). It is considered one of the best varieties grown in Uzbekistan with smaller round to flat-spherical fruits, but sometimes the fruits are large and reach 600-800 g. The peel is thin or medium thick. The arils are medium in size, dark red, sweet and sour. The color of the juice is red to dark cherry, the sugar content is 15.5% and the acid content is 1.9%. The fruits ripen in early October. They are stored for about 3 - 4 months.
Kay-Acik-Anor (Uzbekistan-Tajikistan). The shrub is large. The fruits are large (300 - 400 g), round. They contain up to 16% sugar and 1.4% acids. The fruits ripen in mid-October. The transportability and shelf life of the fruits are good. The productivity of the shrub is up to 50 kg.
Kazake Anor (Uzbekistan). The fruits are large (300 - 400 g), round, greenish-yellow in color. The peel is medium thick, the arils are large. The juice is raspberry-red, sweet and sour, pleasant and contains up to 20% sugar and 1.85% acids. The juice yield is 45%. The fruits ripen in the first half of October. Productivity is high.
Wonderful (California, USA). This soft-seeded variety is the most widespread in the USA, where it occupies more than half of the pomegranate cultivation area. The fruits are small, weighing 180-220 g, but very tasty and sweet. The color of the fruits is white-yellow with a delicate crimson blush. The fruits ripen in early October. The seeds are very small, soft, the juice is light raspberry. Ripe fruits contain 13% sugar and 0.4% acids. The yield is about 15 kg per shrub. The fruits are stored for 2 months.
Siyah Dane (Iran). The fruits are very large, up to 640-700 g, round, dark crimson, light, shiny. The peel is thin. The juice is dark cherry, sweet and sour, delicate, pleasant, its yield is up to 61.89%. The sugar content is 19.63% and the acid content is 1.62%. The fruits ripen in the first decade of October. The yield from a shrub is 35 - 40 kg.
Saveh (Iran). The fruits are large, up to 400 - 600 g, bright red. The peel is thin, red, the juice is dark crimson, sweet and sour, its yield is 52.17%, the sugar content is 19.55% and the acid content is 1.83%. The fruits ripen in mid-October. The yield from one shrub is 30 kg.
Malta (Spain). An excellent dessert soft-seeded variety. The fruits are large, up to 350-400 g, greenish with a bright red blush. The peel is thin. The juice is light red, sweet and delicate, its yield is up to 60.03%. The seeds are soft, edible. The sugar content is 18.0% and the acid content is 1.05%. The fruits ripen in the first decade of October. The yield from one shrub is 32 kg.
Breeding of pomegranate varieties in Azerbaijan
The Goychay Research Station of the Scientific Research Institute of Fruits and Tea of the Ministry of Agriculture of Azerbaijan (SRIFTG) is one of the most important centers of pomegranate genetic resources. Their collection consists of native and bred Azerbaijani varieties, as well as introduced varieties.
Improvement of the pomegranate assortment in Azerbaijan is carried out through clonal selection and hybridization. Thanks to targeted selection, pomegranate varieties have reached a high qualitative level. The result of clonal variability is mutations. Spontaneous mutations in pomegranate and differences from the original variety are manifested in changes in the color and quality of fruits, ripening time, yield and shrub growth. Among the main standard varieties (Pink Guleysha, Gyrmyzy Guleysha, Bala Mursal, Gyrmyzy Gabyk, Nazik Gabyk, Meles-Shelly and VIR) there are plants with both positive and negative deviations. The selection of clones is about improving existing varieties. This requires strict control of varietal purity and intra-varietal selection.
Morphological characteristics of fruits, such as fruit number and yield per shrub, fruit weight and shape, color, as well as juice quantity and quality, are important indicators for selecting a genotype as a commercial product. Experimental data from many breeders have shown the importance of repeated crosses with one of the hybrids or the best varieties. Each new generation carries the characteristics of both parents or ancestors. In the subsequent generation, the healthiest and most productive pomegranate varieties, which are more cold-resistant, were selected. Of the varieties bred by the Azerbaijani SRIFTG, the following two are noteworthy:
Nasimi (Spring x Bala Mursal+Agdam+Gyrmyzy Guleysha+Garabagh). The fruits are medium to large (350 - 400 g), round or flat-spherical, red with cream gaps with red spots, stripes and dots. The skin is thin. The juice with seeds makes up 69.8% of the fruit. The juice is sweet and sour, cherry red, its yield is 59.2%. The sugar content is 18.3%, the acid content is 2.03%. The seeds make up 10.6% of the fruit. The harvest in the 7th year reaches 40 kg per shrub.
Vurgun (Spring x Azerbaijan). The fruits are large (415 g), round, with a basic cream color, with a red covering color throughout the fruit, with stripes and dots. The peel is medium thick, the juice is sweet and sour, dark red, its yield is 53.8%, the sugar content is 18.8% and the acids are 1.98%. The seeds make up 16.8% of the fruit. The harvest in the 7th year is 36 kg per shrub.
Breeding soft-seeded varieties
Pomegranate seeds are usually very hard and unpleasant to eat. Soft-seeded fruits are therefore an advantage. The Azerbaijani variety collection includes the older soft-seeded varieties Malta, Paper, and Iranian. All of these varieties taste sweet but are more sensitive to low growing temperatures than local varieties. Malta is a high-quality variety, but has a non-standard color. Paper is also pale and severely damaged by codling moths. Iranian, cream-colored with a bright red blush, has insufficient juiciness. These older varieties were used for crossbreeding to obtain offspring with better qualities and characteristics. The result of crossing the Paper variety was two seedlings with soft seeds, which were used for subsequent hybridization. In the next period, plants with soft seeds and fruits with sweet juice were selected from the resulting selection offspring. From these, the highest-quality varieties in terms of quality and juice color were bred: Mekhseti, Dessert Azerbaijani, and Aleko.
Mekhseti (Spring x Azerbaijan). The fruits are large (350 - 400 g), round to flat-spherical, dark crimson and bright red. The peel is thin. The yield of juice with seeds is 67.4%. The juice is sweet, delicate, dark raspberry red and has a yield of 56.3%. It contains 20.29% sugar and 0.31% acids. The seeds are small, soft and edible, making up 11.1% of the fruit. The fruits ripen in early October. The yield of a 7-year-old shrub is 26.7 kg.
Dessert Azerbaijani (Azerbaijan x Malta). The fruits are medium to large (350 g), round, dark crimson and red. The peel is very thin. The juice with seeds makes up 71.7% of the fruit weight. The juice yield is 59.3%, contains 17.01% sugar and 0.73% acids. The seeds make up 12.4% of the fruit weight, are soft and edible. The fruits ripen in early October. A seven-year-old shrub produces 22.0 kg of fruit.
Aleko (Spring x a mixture of Bala Mursal + Agdam + Gyrmyzy Guleysha + Garabagh pollen). The fruits are large (500 g), flat to round, intensely crimson-red with subcutaneous light green dots. The peel is thin. The juice is sweet and sour, dark cherry, delicate, reminiscent of wine and very tasty. Its yield is up to 63.5%. It contains 20.8% sugar and 2.01% acids. The seeds are small, soft, elongated, making up 10.1% of the fruit. The fruits ripen in the first decade of October. The yield of a 7-year-old shrub is 28.8 kg.
